Punch



June 3, 1930. A. E. GUERTIN PUNCH Filed July 26. 1928 Patented June 3,1930 AUGUSTUS E. GUEBTIN, I BELMONT, MASSACHUSETTS PUNCH Application lelJuly 26,

My invention relates to punches and particularly to punches Ifor use inmaking gaskets and the like, the object of the mventlon being to providean improved hand punch of this class by means of which bolt holes may beaccurately and expeditiously formed 1n gaskets. It is also an object ofthe invention to provide a hand punch outfit or kit including a singlecutter holder constructed with means whereby to separably couple orconnect a cutter to the same, and a pluralit of clrcular cutters ofvarious sizes, either o which may be coupled to, or connected with, saidholder so as to serve as a complementary part thereof.

To these ends I have providedan lmproved punch, and also an improvedpunchmg outlit or kit, having the peculiar features of construction andmode of operation setV forth 1n the following description, the novelfeatures of the invention being particularly polnted out and deiined inthe claim at the close thereof.

In the accompanying drawings Figure 1 is an elevation, partly 1nsectlon, of my improved punch.

Figure 2 is a view like Fig. 1, butwith the holder and its cutter shownin the posltlons occupied by them at the completion of the cuttingstroke.

Figure 3 is a detail of the spllt ring hereinafter described.

Figure 4 is a sectional detail hereinafter described.

Figure 5 is a view showing a set of cutters for use with the holderhereinafter described.

The main feature of my invention resides in the construction of theimproved punch shown in Figs. 1 and 2 with which I preferably provide aset of complementary cutting tools, or cuttersisuch as shown in Fig. 5.

The punch of Figs. 1 and 2 comprises a body 1 herein shown as a metalbar formed interiorly and at one end thereof with a chamber or socket 2.At its outer 'or lower end the chamber 2 is counterbored to adapt it toreceive a circular cutter 3' that is part of a cutting unit. In Figs. 1and 2 this cutting unit is designated b and in practice I provide ma.serial no. 295,481.

a set of these units of different sizes as shown in Fig. 5.

The circular cutter 3 of each cutting unit is mainly of conical form butat its upper end is made with a cylindrical body portion 4 to t 55Within the counterbore at the lower end of the socket or chamber 2, saidcounterbore providing an annular shoulder 5 which serves as an abutmentfor the inner end of the circular cutter 3. The cylindrical portion 4 is00 formed upon its exterior with a circumferential groove 6 that isoccupied by a split spring wire rin 7 that engages an annular groove 8provi ed in body 1 adjacent the lower or outer end of the chamber 2,thereby to lock the cutter 3 to said body but'with provision for removalof the cutter when changing from a cutter of one size to a cutter ofanother size. Thus by holding the body l and applying endwise force tothe cutter it can ,70 be forced into, or Withdrawn from, the chamber 2,the split ring 7 yielding to permit the same when suiiicient force isapplied as dcscribed.

The cylindrical body portions 4 of all of the 75 cutters of Fig. 5 areof the same diameter so that either one of said cutters may be forcedinto position within the counterbore of the chamber 2 where it is lockedand held against accidental loss by the split ring 7, and when it isdesired to substitute another cutter of another size, the one that is inposition within the holder can be withdrawn and the new cuttersubstituted very uickly;

The cutter 3 of eac cutting unit is an an- 85 nulus made with acylindrical bore Within which is slidably mounted a pilot-ejectorplunger 9 provided at its inner end with a head 10 that is held againstthe 'inner end of the cutter annulus by means of a coiled spring 11within chamber 2. The outer end of the pilot-ejector 9 is preferablybluntly pointed as at 12, and as shown in Figs. 1 and 5 a considerablelength of the outer end portion of each pilot-ejector projects beyondits cutter annulus 3.

Thus, after properly marking on the gasket G the positions of the holesthat are to be punched therein, the axis of the punching tool'shown inFigs. 1 and 2 can be accurate- 100 ly positioned with respect to eachmark by placing the point 12 on the latter. The holder or body 1 is thenpushed downward until the lower cutting edge 13 of the cutter 3 rests onthe gasket G whereupon the upper end of the holder or bod 1 is struckwit a hammer thereby driving t e cutter through the gasket as shown inFig. 2. When the tool is raised from the work the plunger 9 holds thecutout down against the work support W, the

sprin 11 expanding as body or holder 1 is raise until the head 10 at theinner end of the ejector-pilot 9 engages the inner end of the cutterannulus 3.

From the above description it will be clear that I have provided animproved punch which can be expeditiously and accurately operated, theplunger 9 serving the double purpose of a pilot for use in positioningthe punch upon the work, and as an ejector for removing the cut-out fromthe cutting annulus.

It will also be clear that the above described outfit provides simple,inexpensive and efficient means for use in punching several differentkinds of holes in gaskets orthe like.

What I claim is:

A hand punch comprising a body member consisting of a bar of metal madeinteriorly with a chamber that extends to one end of said body, saidchamber being formed to provide an annular shoulder ad]acent said endand to provide an annular groove bet-Ween said shoulder and said end; acutter annulus having a body portion fitting telescopically within theouter end portion of said chamber and against said shoulder, said bodyportion being made upon its exterior with an annular groove reglsteringwith the groove within the chamber, and a resilient spllt ring looselyand permanently occupying the groove of the cutter annulus and removablyconfined within the groove of the chamber to separably hold the cutterannulus within t-he body member, a pilot-ejector plunger slidablymounted within said cutter annulus and provided at its inner end with ahead engaging said annulus to limit its outward movement, and a springWithin said chamber yieldingly holding said plunger at the limit of its'outward movement with its outer end portion projecting beyond saidcutter annulus.

Signed by me at Boston, county of Suffolk, State of Massachusetts, this10th day of J uly,

AUGUSTUS E. GUERTIN.

